FWIW, I saw the alerts this morning for 505 and given dbperry's write-up about turns of equipment figured the 516 would be late. The T alerts verified this fact, so I figured I'd wait at home and catch 516 at Westborough in 45 or so minutes. Turns out it was 1 hour and 3 minutes into the station with a consist of 2 trains according to conductor's announcement apologizing for the delay. Doubles on both ends plus 2 engines(!) but I haven't verified as I got on "in the front". Anyway, as we leave Wellesley Square, we're 1 hour 1 minute late. Nice to have a double to sit in as this usually all singles.

After getting off at Yawkey, I mistook the "doubles on the ends" as the whole train without seeing that this was just P507 and P505 joined together, which I got from reading dbperry's blog about P508's delay because of P505 breaking down. We were riding in the P507 part of P516. And it was not an unpleasant trip at all, unless you had to wait the hour at the station.

Will they de-couple these once they get to South Station? Or does it all depend upon available equipment or other factors?

welp, I'll fill in some details as to what happened to 505. The train worked perfectly going outbound until coming into Wellesley square to make the station stop, and then couldn't take power from the 1026. The Generator Field breaker kept tripping, so no power was being produced to the traction motors. The main engine was still running though....507 with the 2019 came up behind to assist, and the blogger got it right, not 1 MU cable on either train, 508 was kind enough to lend a hand with a spare. The the double draft ran out to Worcester and back, and as stated, train was 63 minutes late on the inbound trip, there was no chance of making up any time. . Once it got to south station, the train was brought over to the yard and the 1026 was cut and brought to BET by the switcher Friday night, and replaced with the 2005 for evening rush hour service

I will rarely complain about equipment breaking down in the field. Maybe only if it is a recurring problem with a particular loco. Although lots of other people believe Keolis and the MBTA don't care and aren't trying, I'm not there. I'm over in the camp about deferred maintenance, underfunding, blah, blah.

However, it seems like there has been a rash of dead locos out on the rails over the past few weeks. I'm sure there are statistics about this somewhere at Keolis - I'd love to see them - and maybe I'm wrong about the frequency. But it's getting harder to accept the 'field breakdowns' - and I'm sure the engineers and conductors are just as frustrated as the passengers.

Anyway, hopefully the MU cable debacle spurs Keolis into implementing extra scrutiny by the terminal maintenance crews (or whoever) to make sure every loco has a MU cable and air hose. Here's an idea:

1) Take a week or a few days for all the locos to cycle through a service stop where staff can insure an MU cable is on board. 2) By that time, every loco should have an MU cable.3) Place one spare MU cable and air hose at the far end of each South Station platform4) Once everything above is in place, never let a set leave South Station without the gear. During the brake test / pre-departure check, the engineer verifies gear is present. If not, he just grabs the spare. Someone can replenish the spare without urgency, and the train isn't delayed awaiting delivery of the spare.

dbperry wrote:South side delays all day 12/23 due to "signal issue between Ruggles and Back Bay" as per @MBTA_CR, which struck me as odd since there is no interlocking there.

You're right -- that is odd. There's not even an automatic block signal in that space. I suppose it is possible that the issue was actually between Cove and the automatics at roughly MP 226. Ruggles to Back Bay would be fully covered by that span. Or perhaps even an issue with the ACES which was specifically limited to Back Bay to Ruggles.